Outgoing Doctor Who showrunner Steven Moffat and his predecessor Russell T. Davies joked about ending the recently concluded season ten with the cliffhanger of Missy becoming pregnant after sleeping with The Master. Season ten’s finale episode, “The Doctor Falls“, was incredibly well-received by fans and featured an on-form Peter Capaldi facing off against an army of Cybermen in one of his final jaunts as The Doctor and (possibly) bidding farewell to his companions Bill and Nardole.

Also featuring in the episode were two versions of classic Doctor Who villain, The Master. Michelle Gomez and John Simm‘s incarnations of the character came face to face and after initially teaming up against The Doctor, Gomez’s Missy ultimately decided to stand with her rival Time Lord and sneakily stabbed her previous regeneration. Sim’s Master quickly returned the favor. Despite killing each other, Missy and The Master had a sizzling chemistry which at times boiled over into sexual tension, with the episode even pulling out an erection joke.

According to RadioTimes however, the relationship between the character’s two regenerations could have been even more intimate. Moffat recounts that when he informed Russell T. Davies, about his intention to bring back John Sim, thoughts quickly turned to potential attraction between the duo and a cruel prank was devised for incoming showrunner, Chris Chibnall, Moffat states:

“He [Davies] is going ‘Oh my god the dialogue! Oh god how brilliant. Oh my god…they’re going to, aren’t they?’ I said Russell, it’s a children’s show… we can’t do that. But we concocted this whole scheme that I’d cliffhanger out of my era on Doctor Who – handing over to Chris [Chibnall] – with Missy telling the Master and the Doctor that she’s pregnant… Over to you Chibs, sort that one out! [laughs]”

Clearly, the plot was never seriously considered but the prank would’ve certainly left the new showrunner with a number of tricky questions to answer. “What happens when your parents are two regenerations of the same person?” and “Will the Master’s child be good or evil?” being two of the first that spring to mind. Furthermore, introducing a new Time Lord character to the show would no doubt have huge ramifications for the future of the show.

In any case, Moffat ultimately ensured Chris Chibnall would be left with a relatively blank slate when the time comes for him to take the reigns. Capaldi’s departure has already been confirmed, Missy has been written out (temporarily, knowing The Master) and the Doctor’s assistants have both been given scenes that could function as departures but also leave the door open for a return.

And some fans will definitely be hoping that some elements of season ten do return after what many consider to be an excellent run. Both Bill and Nardole were fantastic companions and one or both of them would be welcome features in season eleven should Chibnall decide to include some familiar faces.